Best design and manufacturing practice calls for the application of environmental stress screening to:
- All material acquisitions that include electrical, electronic, electro-optical, electromechanical or electrochemical components in demonstration & validation, engineering & manufacturing development and production phases
- Reprocurements and the procurement of spare and repair parts where the cost of ESS implementation can be amortized economically or where ESS was required in original equipment
- Depot overhaul programs where opportunities exist for substantial cost savings and overhaul repair effectiveness
- Nondevelopmental items, such as commercial off-the-shelf (NDI-COTS) and domestic or foreign military (NDI-Military) items only to the extent ESS was implemented and documented during either current or previous production. NDI items are not to be used unless they comply with all specified requirements, including ESS.
- Equipment and spares that have been specifically designated to receive ESS
ESS may be applied at any manufacturing level, from piece parts to end items. It is intended to screen defects in a manner that is not harmful to properly manufactured material. Some components, such as plasma displays, vacuum tubes, etc., by nature of their design, are not amenable to either vibration or temperature screening. Hardware proven to be too fragile may be excluded, but rationale for exclusion must be approved by the government.
